1. Field of the Invention
The present invention relates to coaxial connectors.
2. Related Art
Sometimes, it is necessary for a coaxial connector attached to a circuit board to be movable to a certain extent in a radial direction or an axial direction perpendicular to the plugging direction when the coaxial connector is plugged with a mating connector.
Japanese patent application Kokai No. 7-37648 discloses such a coaxial connector. As FIG. 4 shows, the coaxial connector comprises a plug-side coaxial member 50 to be plugged with a mating connector (not shown) and a base-side coaxial member 60 attached to a circuit board (not shown).
The plug-side coaxial member 50 consists of a dielectric member 51 having a cylindrical section 51A and a pair of extended sections 51B extending radially from the bottom of the cylindrical section 51A, and central and outer conductors 52 and 53 provided so as to cover the inner and outer surfaces of the dielectric member 51. That is, the central and outer conductors 52 and 53 have cylindrical and extended sections 52A and 53A, and 52B and 53B, respectively. In addition, protruded contacts 52C and 53C are provided on the extended sections 52B and 53B, respectively.
The base-side coaxial member 60 has a substantially rectangular dielectric block 61. An upper recess 61A extends from one side to the other side of the dielectric block 61. A central conductor connection member 62 is provided on the bottom of the upper recess 61A and folded back at the both ends of the upper recess 61A. An outer conductor connection member 63 is provided on the dielectric block 61 and has a hole 63A through which the cylindrical sections 51A, 52A, and 53A extend upwardly. It is folded back at the both sides of the dielectric block 61. In this way, the central conductor 52 is shielded by the outer conductor 53.
The protruded contacts 52C and 53C are in spring contact with the central conductor connection members 62 and 63, respectively, and the diameter of the hole 63A is greater than that of the outer conductor 52 so that the coaxial member 50 is movable in the radial direction.
The folded back portions of the inner and outer conductor connection members 62 and 63 are soldered to corresponding circuit conductors of the circuit board. Even if there is a difference in the radial direction between positions of the coaxial member 50 and a mating connector, the coaxial member 50 is moved in the same direction and plugged with the mating connector without producing any stress in the base-side coaxial member 60.
However, the coaxial connector as shown in FIG. 4 has disadvantages that the shielding made by the outer conductor is not perfect and that the characteristics vary with the axial distance between the circuit board and the mating connector.
First of all, as shown in FIG. 4, sides of the outer conductor connection member 63 are opened, and there is no shield on the sides of the central conductor 52 and the central conductor connection member 62. This area is so large that it has large influence on the characteristics of the coaxial connector.
The plug-side coaxial member 50 of the coaxial connector is not axially movable with respect to the base-side coaxial member 60 so that if the distance between circuit boards on which the mating connector and the base-side coaxial member 60 are attached, respectively, is changed, the depth of plugging with the plug-side coaxial member 50 of the mating connector is changed. Consequently, the shield range is changed, resulting in the changed characteristics.